XP in 2020? Not even close. Read the fine print...

Yes, Microsoft is extending downgrade rights for Windows XP. No, you will not be able to buy a PC with Windows XP downgrade rights in 2020. In fact, by my calculations XP will be officially and completely out of all sales channels in less than four years. Here's why.

Yesterday, in a post about Windows 7 and Server 2008 R2 Service Pack 1, Microsoft announced they were extending downgrade rights for Windows XP. I saw the announcement and didn't think much of it. But then I saw that my colleague Mary Jo Foley had picked up on the story last night (Windows XP gets yet another reprieve from Microsoft). She referred to something she had read in ComputerWorld, and I said, "Really? XP is going to still be around in 2020? How could I have missed this?" So I took a second look at the Windows Team blog post, and a closer look at the licensing rules that all these dates are based on, and then I checked in with a Microsoft spokesperson to confirm my calculations.

Here's the short version: ComputerWorld missed a few important details in its calculations and thus reached the wrong conclusion. Yes, Microsoft is extending downgrade rights for Windows XP. No, you will not be able to buy a PC with Windows XP downgrade rights in 2020. In fact, by my calculations XP will be officially and completely out of all sales channels in early 2015.

Microsoft makes it easy to get confused with licensing issues, and the topics under discussion are ones I've written a lot about here in the past. I've already explained how downgrade rights work, and I decoded Microsoft's published support lifecycle for the business versions of Windows back in 2008: How long will Microsoft support XP and Vista? (If the rest of this post gets confusing, it might help to read either or both of those explainers).

Here's what Microsoft announced yesterday, in a post that looked like it was very heavily vetted by lawyers. I've highlighted a few key phrases:

To support our customers’ “unprecedented move” to migrate their PC environment to Windows 7, we have decided to extend downgrade rights to Windows XP Professional beyond the previously planned end date at Windows 7 SP1. This will help maintain consistency for downgrade rights throughout the Windows 7 lifecycle. As a result, the OEM versions of Windows 7 Professional and Windows 7 Ultimate will continue to include downgrade rights to the similar versions of Windows Vista or Windows XP Professional. Going forward, businesses can continue to purchase new PCs and utilize end user downgrade rights to Windows XP or Windows Vista until they are ready to use Windows 7. Enabling such rights throughout the Windows 7 lifecycle will make it easier for customers as they plan deployments to Windows 7.

In the interest of providing more consistency and predictability with how we manage the Windows lifecycle, we are confirming our current policy of allowing retailers to sell the boxed version of the previous OS for up to 1 year after release of a new OS, and that OEMs can sell PCs with the previous OS pre-loaded for up to 2 years after, the launch date of the new OS. This means that since Windows 7 launched on October 22, 2009, retailers will be able to sell the boxed version of Windows Vista until October 22, 2010, and OEMs will be able to sell PCs with Windows Vista preinstalled until October 22, 2011. I also recommend checking out this blog post regarding Windows XP end-of-sales and end-of-support deadlines.

Where ComputerWorld and Gizmodo and many others who've written about this have stumbled is by confusing the technical support lifecycle with the sales lifecycle. Microsoft's technical support lifecycle provides five years of mainstream support for all versions of Windows and five additional years of extended support for business versions of Windows. So yes, Windows 7 will be officially supported with security updates and bug fixes until the end of 2019, which is ten years after it was released.

But here's a much more important support date: April 2014. That's when Windows XP SP3 will reach the end of its support lifecycle and Microsoft will no longer distribute security patches for it. Businesses that deploy Windows XP via downgrade rights after April 2014 will be deploying an unsupported operating system. If you exercise those downgrade rights, you're completely on your own. Do you feel lucky?

And anyway, all this talk of support lifecycles is irrelevant. When Microsoft refers to "the Windows 7 lifecycle" in a discussion of licensing, they mean the completely separate sales lifecycle, which they helpfully explain in the very next paragraph. Remember, downgrade rights apply only when you purchase a new PC with an OEM license for a business edition of Windows (Professional or Ultimate). OEM sales stop two years after the release of the next version of Windows. (Sales of boxed retail copies stop one year earlier.) If you assume that Sinofsky's team will deliver another on-time release, then Windows 8 will hit retail shelves exactly three years after Windows 7, in October 2012. And that's when the clock starts ticking. Two years later, at the end of 2014, Microsoft will no longer permit OEMs to sell Windows 7. Customers can buy Windows 8, which will include downgrade rights to the previous two versions—Windows 7 and Windows Vista. It will not include downgrade rights to XP.

Microsoft could miss that ship date, of course, which would give XP a slight reprieve. But I doubt that will happen. And they could also choose to extend support for Windows XP again. But I don't see that happening, at least not by any significant amount. I could see them extending XP's support life to match the end of OEM sales via downgrade rights—from April 2014 to the end of that year—but sooner or later they have to nail the coffin shut.

Existing copies of Windows XP will not expire, of course. But OEM and volume license copies are tied to the hardware they were first installed on and can't be transferred to new systems. So by the end of 2015 you will no longer be able to buy any version of Windows that includes downgrade rights to XP. That's when XP finally rides off into the sunset for good.